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Sentinel wetlands at Cuyahoga Valley National Park (NP) comprise a set of twenty important management areas and reference sites. These wetlands are monitored more closely than other wetlands in the wetlands monitoring program and are the focus of the volunteer monitoring program for water levels. We used the Ohio Rapid Assessment Method (ORAM) to evaluate habitat in the sentinel wetlands. A total of 37 long-term sample plots have been established within these wetlands to monitor biological condition over time using vegetation as an indicator. Vegetation is intensively surveyed using the Vegetation Index of Biotic Integrity (VIBI), where all plant species within the plot are identified to the lowest taxonomic level possible (genus or species). Sample plots were surveyed twice from 2008 to 2018 and the vegetation data were evaluated using five metrics: VIBI, Floristic Quality Assessment Index (FQAI), percent sensitive plant species, percent invasive graminoids, and species richness. These metrics are discussed for each location. This report also highlights relevant land use histories, common native plant species, and invasive species of concern at each wetland. This is the first report in a two-part series, designed to summarize the results from intensive vegetation surveys completed at sentinel wetlands in 2008–2018. Boston Mills, Virginia Kendall Lake, Stumpy Basin, Columbia, and Beaver Marsh are all in excellent condition at one or more plots. They have unique habitats with some specialized plant species. Fawn Pond is in good condition at most plots and scores very high in comparison to other wetlands within the riverine mainstem hydrogeomorphic class. Metric scores across mitigation wetlands were low. Two of the three wetlands (Brookside and Rockside) are not meeting the benchmarks originally established by the United States Army Corps of Engineers and Ohio Environmental Protection Agency. Krejci is still a young mitigation site and success will be determined over time. Park-supported invasive species control efforts will be crucial for long-term success of these sites and future mitigation/restoration projects. The wetlands monitored because of proposed ecological restoration projects (Pleasant Valley, Stanford, and Fawn Pond) have extensive invasive plant communities. These restoration sites should be re-evaluated for their feasibility and potential success and given an order of prioritization relative to the newer list of restoration sites. Cuyahoga Valley NP has added many new areas to their list of potential wetland restoration sites after these areas were selected, and there may be better opportunities available based on restoration objectives. Restoration goals should be based on the park's desired future conditions, and mitigation goals of outside partners may not always be in line with those. The multiple VIBI plots dispersed throughout the large wetlands at Cuyahoga Valley NP detected and illuminated spatial patterns in condition. Many individual wetlands had a wide range of VIBI scores within their boundaries, sometimes reflecting localized disturbances, past modifications, and management actions. Most often, these large fluctuations in condition were linked to local invasive plant infestations. These infestations appear to be the most obvious and widespread threat to wetland ecosystems within the park, but also the most controllable threat. Some sensitive species are still present in some of the lowest scoring plots, which indicates that invasive plant species control efforts may pay off immediately with a resurgence of native communities. Invasive plant control at rare habitat sites would have large payoffs over time by protecting some of the park's most unique wetlands. Reference wetlands would also be good demonstration sites for park managers to try to maintain exemplary conditions through active management. Through this work, park managers can evaluate the feasibility, effectiveness, and scalability of management practices required to maintain wetland condition. |
